4(18 x)=5(18-x)-搜答案-搜搜考试网

(1)0.25x=-5x=-20(2)3x-4x=1-5x=4(3)3x-4x=18-5x=-13(4)1+7=x+7xx=1(5)9x-7x-3x=-8x=8(6)-x+3x=3-2x=1/2(7)

symsxa=x^4+3*x^3+9*x-18b=x^5-4*x^3-18*x+7c=x^7+6*x^5+9*x^3-5*x^2-2d=x^9-8*x^7+6*x^5-4*x^4+6*x^2+3e=c

是这样的：x^5+x^4=x^3(x^2+x)=(x^2+x)[(x^3-1)+1]=(x^2+x)(x^3-1)+x^2+x=[x(x+1)(x-1)](x^2+x+1)+x^2+x=(x^3-x)

x(1+2+...+9)=x(9-8-7-...-1)x=0记得采纳啊

3/5*X=18X=30再问：详细点。再答：4/5*X-4/5*X*1/4=184/5X-1/5X=183/5X=18X=30

①11x+25=18x+9-5x移项25-9=18x-5x-11x合并16=2x,得出x=8②x+3=4+1/2x两边同乘以2则2x+6=8+x移项2x-x=8-6合并x=2

4x(x-5.07)+x=8.634x-20.28+x=8.635x=8.63+20.285x=28.91x=5.78218-4x=2x+32x+4x=18-36x=15x=2.5(2x-4)*3=(

f(x)=x^5+12x^4+4x^3-2x^2-18x-1=10984f(x)=x(x(x(x(x+12)+4)-2)-18)-1=10984

18x+37=51.418x=14.4x=0.89x-7x=502x=50x=255x+6x=16.9411x=16.94x=1.5412x/4=2412x=24×4x=96÷12x=8

x+3/20x=4623x/20=46x=46x20/23=40,x-1/5x=404x/5=40x=200/4=50,x-1/2x=3/4x/2=3/4x=3/2,x-0.2x=180.8x=18x

x^4-4x^3-4x^2+15x+18=0x^4-3x^3-x^3+3x^2-7x^2+21x-6x+18=0(x-3)(x^3-x^2-7x-6)=0x1=3x2=3.49449283705542

x=-12x=-1x=2/3

设x1=4-√3,x2=4+√3,是方程X^2-8X+13=0的两根所以X1^2-8X1+15=2X^4-6X^3-2X^2+18X+23=(X+1)^2*(X^2-8X+13)+10=10所以原式=

错了吧,是-9x2x²-5x=1原式=15x²-18x+4+3x²-18x+32-9x=18x²-45x+36=9(2x²-5x)+36=9+36=4

1/5x+1/4x*(x-1/4x)=181/5x+1/4x*3/4x=181/5x+3/16x²=1815x²+16x-1440=0x=[-16±√(256+86400)]/30

4x+18=5x-15

4x+18=5x-1518+15=5X-4X33=X

∵x²+3x-2=0∴x³+5x²+4x+18=x(x²+3x-2)+2(x²+3x-2)+22=22

X+5X=18

（5+1）X=186X=18X=3

再问：三道方程再问：x-2/5x=1/10再问：2/3+1/3x=2再问：3x-5X1/3=7/12